Corrosion-inhibiting composition containing cetyl dimethyl amine petroleum sulfonates and method



. lines these has rather obvious shortcomings. exampl n o ves drying o t e-p d uch a so ine,

Unit Sta e P nt ioonnosrommnln o oorn osm N C9N- :TAINING. SGE'PYL prMEfBHYer. mimo- .SHLFQNATES METHOD 'Gharles'W. Varvel, :Bartlesville, Okla, assignor to Petroleum Company,

a corporation of Delaware 7 -No-Drawing. Application July V20, 1956 Serial-No. 598,980

14 Claims. or. 252-391) I i l n i e e t corros onbitin comp stlons and methods. In one aspect th vention relates Phillips to corrosion-inhibiting petroleum or m neral oil compositions. I n another aspectthe invention relates to .a method for inhibiting corrosion of metals in contact 'witlipetroleum oils. In another aspect the invention relates to.a petroleum liquid compositioneontaining up to 0.0;: weight sulfonate.

' An; object of the present invention is to provide petroleumor-miner-al oil' compositions and fuels which protect metals with which they come in contact against rusting and corrosion. Another object is to provide improved fuels containing an elfective corrosion inhibitor which .dcesmt adverse y a f th i b e p p ies of the c1i l or tfuel itself. Still another object is to provide a gnethod ,for inhibiting corrosion ofmetals, especially fer- Qr us metals in contact'with petroleum liquids. Other aspects and objects,.as well as advantages of the invention, will become apparent hereinafter. If e nvention i conc r d hmetho a d o p tions for preventing or retarding corrosion ,of metals,

particnlarly ferrous metals, ,especially'in the presenceof water dissolved or entrained in or settledfrom such petroleunrgils or liquids, including crude oil, lubricating pils, .gasulines, kenoi en n ie u l 11 qdi pa ti larly valuable as applied to prevent corrosion in pipe Qcrrcsion i aue t yoc u nripe l s s a t tc-t and in au om ti nd, imi eq p en bec us .qttraces .of mo sture inev b y p e en in t e t u a lubrieant, ,Gasoline and kerosene, for- .exarnple, as 't-hey leave the refinery are usually free of occluded vr'n oisture,- bntthey can contain as much as 0;0 O 5 to 0.0 ;1 percent .dissq yedm is u Ba o hi d s v mo u separates when the oil is chilled in a storage tank, for instance and e t a the main body of the oil.

waterme so n e o f andl g em al with air through partially filled :tanks -provided with breathendevices. such atank cools, for example at night, the contents contract and air laden .with moisture s pa a iqu d phase bene ipercentg(300 p. p. m-.;) ofeetyl dimethylamine petroleum .enters. This moisture condenses on the walls of ,the

tank, settles to the bottom and dried'air is expelled when the CQntents of thetank again warm-up as from theheat of the sun the next day. 'As will be readily appreciated,

amountsof water at the bottom'of the tank.

.';Although several methodshave been proposed-:foripreventing corrosion in product handling systerns, each }of One method rfor by absorption on dehydrated alumina before the product ,js punaped into pipe lines.- Another method involves theintrgduction into theproductof costly chemicals :such

. ashydrogen or mercaptobenzothiazole which react with dissolved oxygen and thereby arrest corrosion. Still an- ,repetition of thisgcycle eventually leaves appreciable other method involves the introduction of'water soluble V Water-soluble inhibitors are further deficient in many I instances in not affording protection in the oil phase.

According *to the invention there is provided *a com- :position comprising a petroleum liquid orl mineral oil c n ng p to 0.03 ti ercent L t :qetylcd neihy amine petroleum sulfonate. The amounts of my-inhibitor employed are from as little as 0.001 or lessgtejasngneh as 0.03 weight percent, amounts in the range from 0.002 to 0.01 usually beingpreferrcd.

niue t this iu eutid t e e isurn isled a method for preventing or inhibiting corrosion of ferrous metals or non-ferrous .metals which comprises contacting such metals with a petroleum liquid or mineral oil containing up -to-0.0-3 weight percent of cetyl dimethylamine petroleum sulfonate.

.Q ty me yl m ne pe um ulf n t mnl yed the practice of z-thisv invention is difficult to decompose and provides a high degree of protection not only in the oil phase but also in the aqueous phase when ;a separate aqueous phase is present. Moreover, ,my corrosion inhibitor is effective in extremely small iproportions.and over a wide range of temperatures. i c

Any oil soluble petroleum sulfonate can ble usedto prepare cetyl dimethylamine petroleum sulfonate emp ay in the invention; F e amp enniahc anyacids a e u e u in p ep e yl ,dimethy amine-re leum sulfonate. Mahogany acids are prepared by sulfonation of light neutral oils, ahavinglviscosities up to about 50 SUS at 210 F.,fa nd separation of the oilsolublemahoganyacidsfrom the oil-insoluble green acids by a'solvent such as alcohol. Another class of petroleum 'sulfonic acids suitable for the preparation of the cetyl dimethyl amine sulfonate consists of the sulfonic acids prepared by sultonating a dewaxed, deasphalted, solventrefined bright stock having a viscosity in the range of 80. 700 SUSat v2 10" F.

Methods of making cetyl dimethyl amine petroleum ,sulfonate include; (1) the direct neutralization ,pfjpetroleum sulfonic acids with cetyldimethyl amine,-;or (29 i a double decomposition reaction of a s'alt of cetyldia methyl amine with a metal petroleum sulfonate such as sodium or calcium sulfonate. Where directneutralization is em lo ed the reactio .ulqseeds squir rapidu at v.a.1.- q n i te er u e th case ere ;-me a fonates are used as the source of the sulfonate 'i0n,t-he sa as he esqmpqsed w th a m neral sidts a h dm eric i -s l u i .aci iand th n; neutr lia 1th a ba n tro n compou d; si th m a u tan t ,ey

be re d with ana'min t )fo lns a e se ylrsi mine hydrochloride. I

l iietl iil,

' Example I v I;, .a;tviz ea m l sca e prepar tio 10 r tyhdi-methyl @911 .euetre eu sulfpnic acid w s neutral zed ei tti t ,A slight excess eficetyl idin eth-yl amin, was added.

,A; polished rnild sA E 1020 'hot; ol led steel strip 11/2 dneh -,by 5 ginehes 2/ inc-hthick was placed in. a 4 te nce gil samul ba le wi th steerst ip r ting; On -t-he bu uin. ftthei ptt e ;Fi n"m 1 l e s d s dzwater,

s nllf onate e'plaeediin'thebottleand a-cork steppe ins ed in the ZbQttiQ. A small air p ce s A fetentesl J y 2 19.58

s pf f ueL- an'd the-cetyl dime'thylzamine pe- 3 present above the liquid in the bottle. Air was bubbled through the contents of the bottle once a week. The corrosion tests were of 90 days duration.

The tables compare the eifectiveness of cetyl dimethyl amine petrolem sulfonate in the described tests with other amines and with other sulfonates.

TABLE I [Premium gasoline was added to the water.]

Corrosion Additive Corrosion Reduction, Test No. Materiel Tested Conc., Product, Percent p. p. 111. Grams Based on Control Control 0. 0833 None Sultanate C 20 0. 0233 72 d0 40 0. 0154 82 t-Octylamine 40 0. 0710 Aniline Sulfonate 40 0.0492 41 t-Octylamine 40 0. 0970 -17 Sulfonate.

Cetyl dimethyl amine petroleum sulfonate prepared as described from commercial oil-soluble petroleum sulionate.

TABLE II [Aviation gasoline 100/130 was added to the water] Corrosion Additive Corrosion Reduction, Test No. Material Tested Conc., Product, Percent p. p. 111. Grams Based on Control Control 0 0. 2726 None Sulfonate C 40 0. 0495 80 t-Octylaminc 40 0. 1394 42 n-butylamine 40 0. 1490 39 sulfonate. aniline sultonate 40 0. 1478 39 t-octylamine 4O 0. 2l70 l1 sulionate.

1 Cetyl dimethyl amine petroleum sulionate prepared from commercial sultonate.

l Cetyl (limethyl amine petroleum sulfonate prepared from commercia oil-soluble petroleum sulfonate.

Cetyl dimethyl amine petroleum sulfonate prepared using an oil-soluble petroleum sulfonic acid, made by .sulfonating a high molecular weight hydrocarbon fraction inhibited corrosion about the same as the cetyl dimethyl amine petroleum sulfonate prepared from commercial sulfonate. This sulfonate was prepared as follows:

A dewaxed, solvent refined, lubricating oil of 203 SUS at 210 F. and a viscosity index of 93 was sulfonated with 20 percent fuming sulfuric acid in a weight ratio of l to 0.4. The sulfonation was carried out at 130 F. for 65 minutes. This mixture was washed twice with equal volumes of a solution of 90 percent water and 10 percent isopropyl alcohol to remove the acid. Upon adding 90 percent isopropyl alcohol to the washed sulfonated oil, an emulsion formed. Cetyl dimethyl amine was added to this emulsion by titration. Upon neutralization, the oil layer separated out and was removed. The solvent was evaporated. The product was cetyl dimethyl amine petroleum sulfonate.

Cetyl dimethyl amine on a -day corrosion test when dissolved in oil did not show any corrosion inhibition.

Example II In tests conducted in the same manner as in Example I, the following comparative results were obtained:

[Reduction in corrosion based on 10 lbs. inhibitor per 1000 bbl. of oil.]

Percent Reduction in Corrosion Composition Test N o. Inhibitor (Major Compound) Pre- Avgas mium J et Gaso- Fuel line Control. None 0 0 0 Cetyl Dimethyl 80 82 Amine Petroleum Sulfonate. 23 Santolene C (Dimerized 55 45 8 Linoleic Acid). 24 RD119 2 Ammonium 24 Mahoganate. 25 RD 2 Unknown 72 68 0 26 Kontol 77 3 Imidazoline De- 69 57 19 rivative. 27 Alrosperse 100 Unknown 51 62 81 1 Monsanto Chemical Co.

Sinclair Oil Co.

3 Tretolite Co.

4 Geigy Corp.

As will be evident to those skilled in the art, various modifications of this invention can be made or followed in the light of the foregoing disclosure and discussion without departing from the spirit or scope of the disclosure or from the scope of the claims.

I claim:

1. A corrosion-inhibiting composition comprising a pctroleum liquid containing from 10 to 300 p. p. m. of cetyl dimethylamine petroleum sulfon'ate derived from. an oil soluble petroleum sul-fonate.

2. The composition of claim 1 wherein said cetyl dimethylamine petroleum sulfonate is present in an amount from 20100 p. p. m.

3. A method for inhibiting corrosion of ferrous metals in contact with a petroleum liquid and in the presence of moisture which comprises providing from 10 to 300 p. p. m. in said petroleum liquid of cetyl dimethylamine petroleum sulfonate derived from an oil soluble petroleum su'lfonate.

4. The method of claim 3 wherein said cetyl dimethylamine petroleum sulfonate is present in said composition in an amount from 204 00 p. p. m.

5. A composition according to claim petroleum liquid is a crude oil.

6. A composition according to claim petroleum liquid is a lubricating oil.

7. A composition according to claim petroleum liquid is a gasoline.

8. A composition according to claim petroleum liquid in kerosene.

9. A composition according to claim 1 wherein petroleum liquid is jet fuel.

10. A method of claim 3 wherein said cetyl dimethyl amine petroleum sulfonate is prepared from mahogany acids, said mahogany acids being prepared by sulfonation of light neutral oils having viscosities up to 50 SUS at 210 F. and subsequent separation of the oil-soluble mahogany acids from the oil-insoluble mahogany acids by a solvent.

11. A method of claim 3 Wherein said cetyl dimethyl amine petroleum sulfonate is prepared from sulfonic acids prepared by sulfonating a dewaxed, deasphalted, solvent refined bright stock, having a viscosity in the range of 80- 7'00 SUS at 210 F. V

1 wherein said 1 wherein said 1 wherein said 1 wherein said said 12. The method of claim 3 wherein said cetyl dimethyi References Cited in the file of this patent meefieltlrgllsfiastuelfonate is prepared from an oil-soluble UNITED STATES PATENTS 13. A method of inhibiting corrosion of ferrous metal Groom n 1942 pipelines in the presence of moisture which comprises 5 2,533,303 in "1 1950 providing in the petroleum liquid charged to said pipeline 2533304 W 1950 from 10 to 100 p. p. m. cetyl dimethylamine petroleum Zmmer 1952 sulfonate derived from an oil soluble petroieumsulfonate. Oardweu et May 1956 14. A method according to claim '13 wherein said pe- Jones "-v' July 1956 troleum liquid is a gasoline. 10 

1. A CORROSION-INHIBITING COMPOSITION COMPRISING A PETROLEUM LIQUID CONTAINING FROM 10 TO 300 P.P.M. OF CETYL DIMETHYLAMINE PETROLEUM SULFONATE DERIVED FROM AN OIL SOLUBLE PETROLEUM SULFONATE. 